Simple Quaternary Ammonium Ions R4N+ (R=nPr, nBu, nPen) as Versatile Structure Directors for the Synthesis of Zeolite-Like, Heterobimetallic Cyanide Frameworks

The synthesis and crystal structure of [Co(4,4ʹ-bipyridine)2.5(NO3)3]·2C14H10, 1·2C14H10, are presented and discussed in the context of recent developments in the field of coordination polymers. 1 adapts a "molecular railroad" architecture and is closely related to two previously reported molecular railroads in that it contains both bridging and terminal spacer ligands. However, it differs in two important aspects. First, because 1 is uncharged its crystal packing is dominated by stacking interactions between aromatic moieties rather than hydrogen bonding or interpenetration. Second, the resulting open framework planar architecture of 1 sustains coexistence with two topologically complementary sets of phenanthrene molecules. One of these sets can be regarded as a planar network of (4,4) topology whereas the other is an achiral chain of phenanthrene molecules that fills the channels that are generated by the interpenetration of the two planar networks